Grinding mill



p 1967 M. s. SQHAN SKI 3,339,853

GRINDING MILL Filed April 9, 1965 3Sheets5heet 1 Q I INVENTOR My/eo/v J.ff/JCHANSK/ BY 45mm 63M ATTORIE'EYS p 1967 M. s. MISCHANSKI GRINDINGMILL 3 Sheetssheet 2 Filed April 9, 1965 INVENTOR l7/5CHA/VJK/ @MAW -Sept. 5, 1967 VI GRINDING MILL Filed April 9, 1965 .lll! 25 r 82 i a? I0 78 o T Li 1 I I I 7| 32 80 5: 1 62 M. s. MISCHANSK! 3,339,853

5 Sheets-Sheet 3 United States Patent 3,339,853 GRINDING MILL MyronSteven Mischanski, 27 Englewood Road,

. Clifton, NJ. 07012 Filed Apr. 9, 1965, Ser. No. 449,678 9 Claims. (Cl.241-110) ABSTRACT OF THE DISCLOSURE A grinding mill having an uprightcasing with a cylindrical grinding ring therein. A plurality ofarcuately spaced grinding rollers are supported on arms hingedlyconnected to a block mounted on a rotatable main shaft. Fluid cylinderand piston combinations are adapted to impart outward thrust against therollers.

This is a continuation-in-part application of my application Ser. No.338,119 filed Jan. 16, 1964, now abandoned.

This invention relates to grinding mills for comminuting solid materialand, in particular, to mills of this character which employ fluidpressure responsive components for controlling the pressure of grindingrollers against the inner face of a grinding ring.

It is known that .the size and dimensions of the rollers in grindingmills utilizing centrifugal and fluid pressure forces are importantfactors in determining their operative efiiciency both in terms ofproduction rate and power requirements. In general, it may be said thatthe heavier the rollers, the greater the. grinding pressure due tocentrifugal force for a given rate of roller rotation on the grindingring, thus permitting diminished rotation rates for attaining thedesired production rates, and the larger the rollers, the larger theparticles of material that maybe accommodated in the nip defined by theroller surface and the grinding ring. It has been found that in a millusing forced air to remove the pulverized material output actuallyincreases at the reduced rates of rotation permitted by the largerrollers because there is less air turbulence in the grinding regions ofthe mill.

In machinery design, space requirements will frequently dictate the sizeof components. It was discovered that by suspending the rollers frompivotal elements which are located above the region bounded by thegrinding ring and the block on which the elements are mounted additionalspace is afforded in this region to accommodate the larger size rollers.The pivotal movement of the principal operating elements dispenses withthose mechanical problems inherent in sliding parts which have a supportfunction, such problems resulting from the heat of friction, speciallubrication requirements, cocking of elements out of their intended lineof action, sealing, etc.

In one form of the invention there is provided a plurality of cylinderand piston combinations supported by the block, each piston beingadapted to impart outward thrustto one of the rollers to urge it againstthe grinding face, and means areprovided. for admitting fluid underpressure into the cylinder for imparting such thrust.

In another form of the invention, opposed grinding rollers areinterconnected by a single cylinder and piston combination so thatmovement of the piston exerts an outwardly directed thrust against eachof its corresponding rollers.

4 In still another form of the invention, adjacent grinding rollers areinterconnected by a single cylinder and piston combination so thatmovement of the piston simultaneously exerts an outwardly directed forceagainst each .of the rollers. Each of the rollers is provided withangular brackets for mounting the cylinder and piston combination, theangle being dependent upon the number of 3,339,853 Patented Sept. 5,1967 rollers employed. For example, if a total of 4 rollers are Afeature of the invention resides in the provision of a new and improvedgrinding mill which requires considerably less space for mounting therollers. That is, substantially less space is required betweendiametrically opposite rollers than heretofore thought necessary.

Another feature of the invention resides in the elimination of elementsheretofore considered necessary for actuating the rollers in anoutwardly direction. It is intended by the invention to eliminate thenumber of fluid pistons and cylinders and their mounting means requiredto exert thrust against the rollers.

Still further, another feature of the invention is the provision of anew and improved grinding mill which relieves stresses acting upon thecentral shaft, thereby providing a machine having a longer life withless maintenance costs. Further, according to the present inventioncovering means may readily be positioned over the piston rod assembly inorder to maintain a substantially dustfree'environment.

v A further feature of the invention resides in the provision of a newand improved grinding mill which is designed to enhance operatingefiiciency, whichis reliable, compact, durably constructed, practicaland economical.

There has thus been outlined rather broadly the more important featuresof the invention in order that the detailed description thereof thatfollows may be better understood, and in order that the presentcontribution to the art may be better appreciated. There are, of course,additional features of the invention that will be described hereinafterwhich will form the subject of the claims appended hereto. Those skilledin the art will appreciate that the conception on which this disclosureis based may readily be utilized as the basis for the designing of otherstructures for carrying out the several purposessof the invention. It isimportant, therefore, that the claims be regarded as including suchequivalent constructions as do not depart from the spirit and scope ofthe invention. Several embodiments of the invention have been chosen forpurposes of illustration and description, and are shown in theaccompanying drawings, forming a part of the specification, wherein:

FGURE l is a section showing the improved grinding mill whichis taken online 1-1 of FIGURE 2,

FIGURE 2 is a section taken on line 2-2 of FIG- URE 1;

FIGURE 3 is a partial vertical section taken on line 3-3 of FIGURE 2 onan enlarged scale;

FIGURE 4 is a sectional view similar to FIGURE 2, but showing anotherembodiment of the invention; and

FIGURE 5 is a sectional view similar to FIG. 2 but showing still anotherembodiment of the invention.

In the embodiment of the invention illustrated in FIG- URES 1 to 3, thegrinding mill includes a block 2, serving to support the principalcomponents of the mill, which is keyed to the main shaft 4. A bevel gear6 is 'splined to the shaft 4 and is in turn driven by a pinion 8 mountedon the end of pinion shaft 10. Secured to the other end of the vmainshaft 4 is a housing 12 having an internal air chamber 14 whichcommunicates with an air supply (not shown) through conduit 16 whichturns with the main shaft. The conduit 16 is provided with a swivelcoupling (not shown) intermediate its length, the upper portion of theconduit 16 above the coupling being stationary.

Secured to the block 2 and overhanging each of its four sides is acylinder supporting plate 18. On each plate is disposed a cylinder 20having an internal piston 21. To each of the four corners of the block 2is integrally secured an ear 22 within which is disposed a stationaryshaft 24. Journalled on each of the shafts 24 is housing 25 of rollersupporting arm 26 supported in bearings above boss 27 atop ear 22, thearm being intermediately bent to accommodate the piston bearing on itsfree end. In another embodiment of the invention, as best seen in FIGURE4, supporting arms 26 are provided with brackets 78 and 80, as shown. Asingle cylinder 82, piston 84 and piston rod 86 interconnects brackets78 and 80, respectively, cylinders 82 being fixedly mounted on brackets78 and piston rods 86 being pivotally mounted on brackets 80 by means ofclevis 88. It will be appreciated that one cylinder, piston and pistonrod is positioned slightly above the other cylinder, piston and pistonrod in order for them to cross over without interfering with each other.This embodiment has several advantages, for example, less space irequired for one than is required for two cylinder and pistoncombinations so that the space required between opposing rollers isthereby reduced. This is particularly important in small size grindingapparatus. Further, economical savings are encountered with thisembodiment due to the elimination of onehalf of the number of pistons,cylinders, piston rods and mounting means therefor. Moreover, accordingto this embodiment of the invention there is less stress on the centralshaft 4 due to the balancing effect between opposed rollers. Forpurposes of preventing dirt, dust or foreign matter from coming intocontact with the piston push rods 86, a stocking 90 may readily befitted thereover as shown by the dashed line in FIG. 4.

In still another form of the invention, as seen in FIG. 5, rollersupporting arms 26 are provided with inwardly projecting brackets 92 and94. Adjacent brackets 92 and 94 are interconnected by a single cylinder96, piston 98 and piston rod 100, cylinder 98 being fixedly attached tobracket 92 and piston rod 100 being pivotally attached to bracket 94.This embodiment also has certain advantages including the elimination ofelements heretofore deemed necessary.

As best seen in FIGURE 3, a hose 27a is slipped over the boss 27 withthe upper end thereof disposed over a hub depending from housing 25 ofthe arm 26 and is provided with hose clamps to seal off the bearingswhich are similar to those provided for in the four grinding rollers 22described below. A cover plate 29 bolted to the housing 25 seals thelatter against the entrance of dust. Integrally extending from the freeend of each arm is a vertical hub 28 within which is housed stationaryshaft 30. The hubs 28 are supported by their respective armssubstantially above the top surface of block 2 virtually extended.

Grinding rollers 32 are supported in bearings on the respective shafts30 and are adapted to engage grinding ring 34 carried on the innersurface of the casing 36 of the mill. The grinding rollers are supportedfor rotation on upper and lower bearing rollers 38 and 40, respectively,disposed between inner races 42 and 44 respectively, and outer races 46and 48, respectively. A spacer 50 supports the outer races and spacer 52supports the inner races. Spanner nut 54 and nut 56 and lock washer 57on threaded extension 58 of the shaft 30 maintains the hearingassemblies in proper relation to the shaft and the grinding rollers. Theinterior of the rollers is kept dust free by means of bottom cap 60 andtop seal 62 which is filled with packing material about the shaft 30.

Each of the cylinders 20 is in communication by means of conduit 64 withthe air chamber of the housing 12. Similarly, cylinders 82 (FIG. 4) and96 (FIG. are in communication with an air supply source. Theaccumulative forces acting on the rollers arising from centrifugalforce, which is a function of roller mass and velocity, and air pressurecan be precisely controlled depending on the material being ground andthe degree of pulverization desired by regulating the pressure of theair supply. The total absence of roller supporting structure in thespace between the rollers and the block 2 permits of larger size rollersthan have been used heretofore which reduces the velocity of rollerrotation required to attain a given centrifugal force. Obviously fluidsother than air may be used in the cylinders.

The material to be ground is fed into a hopper 67 affixed to the mill atone side thereof and is forced into the mill by a rotary mountedimpeller 68 driven by any desired means (not shown). A deflector plate69 is bolted or otherwise aflixed to the upper portion of the casing fordeflecting the material downwardly between the grinding ring androllers.

The comminuted material is drawn ofl upwardly through the casing bymeans of a cyclone collector connected by piping (not shown) with thetop of the upper portion thereof. Air for the upward flow of thecomminuted material is drawn into the mill by the cyclone collectorthrough a series of radially arranged openings 70 in the lower portionof the casing and which openings are provided with grills 71 or othermeans for regulating the quantity of air admitted through the openings.The coarse material falls onto a platform 72. A series of arms 75 havingplow shaped free ends 76 are bolted or otherwise aflixed to the block 2and rotates therewith for throwing the coarse material upwardly betweenthe grinding rollers 32 for additional grinding action.

From the foregoing it will be seen that I have conceived a novel andhighly desirable grinding mill for comminuting solid material.

Although several embodiments of the invention are herein disclosed forpurposes of explanation, further modifications thereof, after study ofthis specification, will be apparent to those skilled in the art towhich the invention pertains. Reference accordingly should be had to theappended claims in determining the scope of the invention.

What is claimed and desired to be secured by Letters Patent is:

1. In a mill for comminuting solid material, a casing supported inupright relation, a cylindrical grinding ring supported by said casingand having a peripheral inner grinding face, a plurality of arcuatelyspaced grinding rollers adapted to engage said inner grinding face, arotatable main shaft, a block mounted on said shaft, said rollers beingsupported by arms secured to one end of said rollers, said arms beinghingedly connected to the block, a plurality of cylinder and pistoncombinations, each of said pistons being adapted to impart outwardthrust against said rollers, means for admitting fluid under pressure insaid cylinders for imparting said thrust, and means for driving saidshaft in rotation.

2. In a mill for comminuting solid material, a casing supported inupright relation, a cylindrical grinding ring supported by said casingand having a peripheral inner grinding face, a plurality of arcuatelyspaced grinding rollers adapted to engage said inner grinding face, arotatable main shaft, a block mounted on said shaft, said rollers beingsupported by arms secured to one end of said rollers, said armsv beinghingedly connected to the block, a plurality of cylinder and pistoncombinations, opposed rollers being interconnected by a single cylinderand piston combination, means for admitting fluid under pressure intosaid cylinders for imparting outwardly directed thrust against saidopposed rollers respectively, and means for driving said shaft inrotation.

3. In a mill for comminuting solid material, a casing supported inupright relation, a cylindrical grinding ring supported by said casingand having a peripheral inner grinding face, a plurality of arcuatelyspaced grinding rollers adapted to engage said inner grinding face, arotatable main shaft, a block mounted on said shaft, said rollers beingsupported by arms secured to one end of said rollers, said arms beinghingedly connected to the block, a plurality of cylinder and pistoncombinations, adjacent rollers being interconnected by a single cylinderand piston combination, means for admitting fluid under pressure intosaid cylinders for imparting outwardly directed thrust against saidadjacent rollers respectively, and means for driving said shaft inrotation.

4. In a mill for comminuting solid material, a casing supported inupright relation, a cylindrical grinding ring supported by said casingand having a peripheral inner grinding face, a plurality of arcuatelyspaced grinding rollers adapted to engage said inner grinding face, arotatable main shaft, a block mounted on said shaft, said rollers beingsupported by arms secured to one end of said rollers, said arms beinghingedly connected to the block, a plurality of cylinder and pistoncombinations supported by said block, each of said pistons being adaptedto impart outward bias on one of said rollers against said grindingring, means for admitting fluid under pressure in said cylinders forimparting said thrust, and means for driving said shaft in rotation, thehinged connection of each of the arms being above the top surface of theblock whereby said rollers may be suspended in the annular space definedby the ring and the block free of roller supporting structure betweensaid rollers and said block.

5. In a mill for comminuting solid material, a casing supported inupright relation, a cylindrical grinding ring supported by said casingand having a peripheral inner grinding face, a plurality of arcuatelyspaced grinding rollers adapted to engage said inner grinding face, arotatable main shaft, a block mounted on said shaft, said rollers beingrotatably supported on upwardly extending axes by arms secured to oneend of said rollers, said arms being hingedly connected to the block, aplurality of cylinder and piston combinations, said pistons beingadapted to impart outward bias on said rollers, means for admittingfluid under pressure in said cylinders, for imparting said bias, andmeans for driving said shaft in rotation, the hinged connection of eachof the arms being above the top surface of the block whereby saidrollers may be suspended in the annular space defined by the ring andthe block free of roller supporting structure between said rollers andsaid block.

6. In a mill for comminuting solid material, a casing supported inupright relation, a cylindrical grinding ring supported by said casingand having a peripheral inner grinding face, a plurality of arcuatelyspaced grinding rollers adapted to engage aid inner grinding face, arotatable main shaft, a block mounted on said shaft, said rollers beingrotatably supported on vertically confined axes by arms secured to oneend of said rollers, said arms being hingedly connected to the block inoffset relation from the axes of the rollers respectively, a pluralityof cylinder and piston combinations supported by said block, each ofsaid pistons being adapted to impart outward bias on one of said rollersagainst said grinding face, means for admitting fluid under pressure insaid cylinders for imparting said bias, and means for driving said shaftin rotation, the hinged connection of each of the arms being above thetop surface of the block whereby said rollers may be suspended in theannular space defined by the ring and the block free of rollersupporting structure between said rollers and said block.

7. In a mill for comminuting solid material, a casing supported inupright relation, a cylindrical grinding ring supported by said casingand having a peripheral inner grinding face, a plurality of arcuatelyspaced grinding rollers adapted to engage said inner grinding face, arotatable main shaft, a block mounted on said shaft, said rollers beingrotatably supported on upwardly extending axes by arms secured to oneend of said rollers, said arms being bent and hingedly connected to theblock in offset relation from the axes of the rollers respectively, aplurality of cylinder and piston combinations, each of said pistonsbeing adapted to impart outward bias on said rollers against saidgrinding face respectively, means for "admitting fluid under pressure insaid cylinders for imparting said outward bias to said pistonsrespectively, and means for driving said shaft in rotation, the hingedconnection of each of the arms being above the top surface of the blockwhereby said rollers may be suspended in the annular space defined bythe ring and the block free of roller supporting structure between saidrollers and said block.

8. In a mill for comminuting solid material, a casing supported inupright relation, a cylindrical grinding ring supported by said casingand having a peripheral inner grinding face, a plurality of arcuatelyspaced grinding rollers adapted to engage said inner grinding face, arotatable main shaft, a block mounted on said shaft, said rollers beingrotatably supported on upwardly extending axes by arms secured to oneend of said rollers, said arms being bent and hingedly connected to theblock in off-set relation with the axes of the rollers respectively, aplurality of cylinder piston combinations, the arms rotatably supportingopposed rollers being interconnected by a single cylinder, piston andpiston rod combination, said cylinder being mounted on one of said armsand said piston rod being pivotally connected to the other of said armsrespectively, means for admitting fluid under pressure into saidcylinder for imparting outwardly directed thrust against said opposedrollers respectively, and means for driving said shaft in rotation, thehinged connection of each of the arms being above the top surface of theblock whereby said rollers may be suspended in the annular space definedby the ring and the block free of roller supporting structure betweensaid rollers and said block.

9. In a mill for comminuting solid material, a casing supported inupright relation, a cylindrical grinding ring supported by said casingand having a peripheral inner grinding face, a plurality of arcuatelyspaced grinding rollers adapted to engage said inner grinding face, arotatable main shaft, a block mounted on said shaft, said rollers beingrotatably supported on upwardly extending axes by arms secured to oneend of said rollers, said arms being bent and hingedly connected to theblock in off-set relation from the axes of the rollers respectively,each of said arms supporting inwardly projecting brackets, adjacentbrackets being pivotally interconnected by a single cylinder piston andpiston push rod respectively, means for admitting fluid under pressureinto said cylinder for imparting outwardly directed thrust against saidadjacent rollers respectively, and means for driving said shaft inrotation, the hinged connection of each of the arms being above the topsurface of the block whereby said rollers may be suspended in theannular space defined by the ring and the block free of rollersupporting structure between said rollers and said block.

References Cited UNITED STATES PATENTS 8/1920 Stout 241-131 3/ 1962Mischanski 24l131

1. IN A MILL FOR COMMINUTING SOLID MATERIAL, A CASING SUPPORTED INUPRIGHT RELATION, A CYLINDRICAL GRINDING RING SUPPORTED BY SAID CASINGAND HAVING A PERIPHERAL INNER GRINDING FACE, A PLURALITY OF ARCUATELYSPACED GRINDING ROLLERS ADAPTED TO ENGAGE SAID INNER GRINDING FACE, AROTATABLE MAIN SHAFT, A BLOCK MOUNTED ON SAID SHAFT, SAID ROLLERS BEINGSUPPORTED BY ARMS SECURED TO ONE END OF SAID ROLLERS, SAID ARMS BEINGHINGEDLY CONNECTED TO THE BLOCK, A PLURALITY OF CYLINDER AND PISTONCOMBINATIONS, EACH OF SAID PISTONS BEING ADAPTED TO IMPART OUTWARDTHRUST AGAINST SAID ROLLERS, MEANS FOR ADMITTING FLUID UNDER PRESSURE INSAID CYLINDERS FOR IMPARTING SAID THRUST, AND MEANS FOR DRIVING SAIDSHAFT IN ROTATION.